Exhaust mufflers



March 2l, 1961 L. D. BAKKE ErAL EXHAUST MUFFLERS Filed Aug. l, 1957 O \Oon INVENTORS LAURENCE D. BAKKE RAYMOND A.D|TTMER BY 5&4@ ATTORNE S .NGE

Y 22x55 .EXHAUST MUFFLERS f Detroit, Mieli.,` assignorst ContinentalMotors Corporation, Muskegon,`Mich., 'a corporation of Virginia Thisinvention relates to exhaust mufllerslfor yinternal combustion enginesand more particularly to a Simplified and effective muffler for smallengines such as are used in compressors, starters, lawnmowers, and thelike.

In the development of such small engines, simplicity and economicalmanufacture without sacrificing quality are highly important, and itwillbe noted that many small engines lack mufllers entirely while manyothers have mufllers that are either ineffective, expensive, easilydamaged, dilllcult and costly to assemble and repair, or conducive toconsiderable back pressure if not properly constructed. l

An object of the present invention is to improve small internalcombustion engines by providing a simplified mufller having a minimumnumber of parts.

^ Another object of the invention is to improve small engine mufllerconstruction by providing a mufller casing directly attachable to thecylinder head without the use of adapters or extraneous parts.

A Ifurther object of the invention is to further muffler manufacture byconstructing a rn'ufller` having readily stamped parts and arranged forsimple and rapid' assembly to the engine.

A still further object of the invention is to improve mufflerconstruction by providing simplified parts assembled in such a manner asto give greatest structural strength.

For a more complete understanding of the invention, reference maybe hadto the laccompanying drawing illustrating a preferred embodiment of theinvention in which like reference characters refer to like partsthroughout the several views and in which Fig. 1 is a front elevationalview of the mulller assembly constructed in accordance withtheinvention.

Fig. v2 is an end elevational view of the mufller and afragmentaiyportion of the cylinder head, and

Fig. 3 is a cross-sectional view taken substantially on the line -3-3o-f Fig. ,1.

An internal combustion engine cylinder head is illustrated as havingconventional air cooling fins 11 and an exhaust port opening 12. Amuffler structure 13 is secured to the cylinder head 10 by bolts 14 orsimilar attaching means, and comprises a casing assembly preferablyconstructed of an inner plate member 15 and an outer body member 16,preferably secured together by means of a crimped edge 17 and definingan elongated mufller chamber 13a therebetween, as shown in Fig. 3.

The inner plate member 15 has an extruded pocket portionv 18, in theapproximate center of which is provided an inlet opening 19 arranged toregister with the cylinder head exhaust port opening l12, as illustratedin Fig. 3. Also in Figs. 2 and 3 will be seen how the provision of theextruded pocket portion 18 permits the remainder of the inner plate 15to clear the cylinder head fins 11'which are adjacent the exhaust portopening 12, thus eliminating the need for a special adapter between themufller and the cylinder head.

v The muffler body member 16 is provided with an exi vUnited StatesPatent() 2 haust outlet opening preferably in the form of louvered slots25 disposed in the outer face of the body member "16 and laterallyoffset from the inner plate inlet port 19.

A tubular element 26, preferably cylindrical in shape and provided withperforations 26a is seated in the pocket r18 and encloses a portion ofthe chamber 13a immedi- .ately' Vadjacent the inlet opening 19. Thebaille element 26, preferably is substantially concentric with thecenter of the inletopening 19, and extending to the outer facesupportfor thegbody member 16. 'f

of'theibody member 16v it lservesias, a spacer, providing The boltsf14fextend'through the-outer face-of the body member 16 and the pocket18 into the cylinder head 10 adjacent the exhaust port openinglZ, andare thus preferably enclosed by the baille element 26. The bailleelement 26 is spaced from'the peripheral side of the body member 16 topermit unrestricted flow of exhaust gases into the chamber 13a. Exhaustilow thus is from the exhaust port opening 12 into the interior of saidbaffle element 26, through the perforations 26a into the mufller chamber`13a and out the openings 25.

Although We have described but one preferred embodiment of theinvention, it will be apparent to one skilled in the art to which theinvention pertains that various changes and modifications may be madetherein without departing from the spirit of the invention or the scopeof the appended claims.

We claim:

l. An exhaust mufller for an internal combustion engine having a finnedcylinder head provided with an exhaust port, said mufller comprisingsubstantially oval shaped inner and outer walls and a peripheral sidewall defining a substantially lflattened laterally elongated chamber,one end of said inner wall having an inlet opening communicating withsaid exhaust port, said outer wall having an outlet opening disposedopposite the other end of said inner wall and thereby being laterallyoffset from said inlet opening, a tubular baille member longitudinallysandwiched between said inner and outer walls and peripherally enclosingonly a portion of said chamber directly adjacent said inlet opening,said baille member comprising a tubular structure having inner and outerends respectively abutting the inner and outer walls of said mufflerwhereby said baflle member is retained by and between said walls, andmeans securing said mufller to said cylinder head, said mulllerextending laterally with respect to said exhaust port.

2. The mulller as defined in claim l and in which said inner Wallcomprises a substantially flat oval face plate having an axiallyoutwardly extruded pocket in the end having said inlet opening, saidpocket directly abutting said cylinder head 'at the exhaust port wherebythe remainder of said `face plate overlies and is closely spaced withrespect to the cylinder head fins adjacent said exhaust port.

3. The muffler as defi-ned in claim 2 and in which the inner end of saidbaille member is seated in said pocket and has a peripheral edgecontacted by the inner periphery of said pocket, said pocket therebypreventing lateral displacement of said baille member.

4. An exhaust muiller for an internal combustion engine having a finnedcylinder` head provided with an exhaust port, .said muffler comprisingsubstantially oval shaped inner and outer walls and a peripheral sidewall defining a substantially flattened laterally elongated chamber, oneend of said inner wall having an inlet opening communicating with saidexhaust port, said outer wall having an outlet opening disposed oppositetheother end of lsaid inner wall and thereby being laterally offset fromsaid inlet opening, a tubular baffle member longitudinally sandwichedbetween said inner and outer walls and Patented Mar. 21, 1961peripherally enclosing only a portion of said chamber directly adjacentsaid inlet opening, and means securing said nluler to said cylinderhead, said muffler extending laterally withV respect to said exhaustport, said inner wall comprising a substantially kflat oval face platehaving an axially outwardly extruded pocket in the end having said inletopening, said pocket directly abutting said cylinder head at theexhaust. port whereby the remainder of said face plate overlies and isclosely spaced with respect'to the cylinder head ns adjacent saidexhaust port, the inner end of saidA bafel member being seated in saidpocket, said pocket therebyy preyenting lateral displacement of saidbale member, andsaid baile comprising a substantially cylindricalperforated element disposed substantially concentric withl thecenter ofsaid inlet opening, said meanssecuringsaid muer to said cylinder headcomprising bolts extending through said outer wall and said pocketinto'said cylinder head, said bafe element extendingV from said pocketto said' outer wall and serving to support same against deformation ontightening said bolts.

References Cited in the tile of this patent UNITED STATES PATENTS659,834 Thamsen Oct. 16, 1900 953,778 Cordle Apr. 5, 1910 1,680,671Eschholz Aug. 14, 1928 1,884,452 Weigman Oct. 25, 1932 1,993,863' Smallet al. Mar. 12, 1935 2,050,581 Orem Aug. 11, 1936 2,838,129 Hesse et al.June l0, 1958 FOREIGN PATENTS 212,796 Great Britain Mar. 20, 1924 OTHERREFERENCES German application Ser. No. E7620, printed May 24, 1956(Ia/46c).

